GM is no longer making the T-Type center caps, they I think are still available from them but list price is over $80 a piece for them. I think they are still making the 86/87 Grand National centercaps. A great alternative for the T-Type center cap is the center caps that came on the aluminum Trans Am/Firebirds of the 80's to early 90's. The hole they fit is the same size as what is on our T-Type rims, and you can pick up a set of black or chrome reproduction ones up off ebay for $25. They dont come with center emblems installed so you can use what ever you want. I would suggest going the route I did which was to contact Mark at buickgn.com and he sells several different varieties of center emblems that will fit the Trans Am caps, and he even sells a center emblem that looks very close to the original black and grey Buick Tri-Shield. I think they look great. If youd like I can take some pics of them installed on my wheels.
Per GM Parts Direct, GM list is currently $90.85. GM Parts Direct current price is $53.60 & &12.86 Shipping & handling, bringing the total to $66.46 to your door. These parts are made in Canada, which is probably one of the reasons, or the main reason that thye are so expensive. I bought 4 brand new in the box about 1.5 years ago from one of the higher priced dealers on tb.com, and had them to my door for about $ 265 or so for 4. At that time, I could have had them to my door from GM parts for about $240 or so. As the tooling has already been made for these parts, I would think that GM will make them as long as there is a market for them, and as long as they do not have to make new tooling. They would be foolish not to. Turbofish38 (Eric Fisher, I believe)on this board can tell you whether they are still being made or not, and maybe how many they have on hand. My guess is that they only continue to sell them because we continue to buy them.