If your unit wants you to wear the unit awards, do you have to buy them yourself or are they supposed to give them to you?

SSG Robert Webster - it's the other way around. Permanent wear Unit Awards those the individual soldier is authorized based on being assigned to the unit during the award period. Temporary wear are those that he unit has earned and are worn by soldiers while assigned.

AR600-8-22 March 2019
7–2. Announcement of unit awards
a. All unit awards approved at HQDA will be announced and confirmed in AGOs.
b. During wartime, commanders authorized to approve unit awards will announce awards in POs of their headquarters and forward a copy (electronic preferred) of each order to Commander, U.S. Army Human Resources Command (AHRC–PDP–A), 1600 Spearhead Division Avenue, Fort Knox, KY 40122–5408. A copy (electronic preferred) of the POs will be sent to the U.S. Army Center of Military History (AAMH–FPO), 102 4th Avenue, Bldg 35 (Collins Hall), Fort Lesley J. McNair, Washington DC 20319–5060. POs published to announce the award of a unit decoration will contain the citation of the award, official designation of the unit or units, and inclusive dates. These awards will be con- firmed in AGOs.
c. Commanders must ensure that unit awards that are submitted by the parent organization are coordinated with subor- dinate elements to ensure that subordinate units will not submit duplicate recommendations for unit awards.
d. An approved unit award is for the designated unit and is authorized to members of that unit who participated in the cited action. Personnel who did not participate in the designated action, but who are assigned to the cited unit, are author- ized temporary wear of the unit award. Additional information on wearing unit award emblems is contained in AR 670–1 and DA Pam 670–1.

LTC Jason Mackay - I know what the regulation states.
I was using myself as an example in two different instances. In both instances I was a member of the unit during the period of the citation, and participated in the cited action/achievement. In one case, I had departed the unit and then returned and was in the unit when it was officially presented. In the second case, I had departed the unit assigned to another unit and then retired before the award was given. In both cases I was a member of the units during the citation periods.
The first one was for the MUC awarded to the 1st Battalion 325th Infantry for the period of 10 Aug 1990 to 11 Mar 1991 (DS/DS), DAGO 1994-27 (Dated 27 December 1994), the ceremony was in 1995 after I had returned to the parent unit of the Battalions cited, the 2nd Brigade, 82nd Airborne Division (AKA 325th AIR).
The second one was for the Army Superior Unit Award awarded to the United Nations Command Joint Security Force-Joint Security Area for the period of 1 Aug 1993 to 1 Aug 1994, DAGO 1996-01 (Dated 31 March 1996), basically two (2) months after I retired.
While looking up this information, I found that I have a third one that I did not know about until checking which DAGO's were applicable.
The third on was for the Army Superior Unit Award awarded to the United Nations Command Security Battalion - Joint Security Area for the period of 1 Sep 1994 to 1 Sep 1995, DAGO 1997-14 (Dated 11 April 1997), about 14.5 months after my retirement.

So for me one Meritorious Unit Commendation and the Army Superior Unit Award with one (1) bronze oak leaf cluster.

So what did I get incorrect? Other than I need to have my records updated and get a DD Form 215. To reflect the two (2) ASUAs not on my records.

SSG Robert Webster -
permanent wear = I was assigned to the unit when the unit citation was earned. Now I can wear it forever.
Temporary wear = I am assigned to the unit after the fact and am authorized to wear the unit citation while assigned to the unit.

Not doubting your unit awards authorized.

LTC Jason Mackay - I think that we are beginning to be confused about the subject.
Bottom line - Whether the unit award is permanent or temporary it is initially issued through the unit supply room either directly or indirectly; whereas indirectly is through the unit S1 or Human Resources, though it is acquired or requisitioned through the supply room/system. Or it is supposed to be in accordance with regulations.

But you have to give it back when you leave.

Except, of course, that it doesn't always happen (it almost never happened in my years of active service, and obviously it still isn't happening or the question would not have come up).

There are a lot of things that are supposed to be done by units that simply never happen in most units.