I would think living in the great State of Tx you would have plenty of old junkyards to dig around in. If not, you must have some decent sized car swap meets where these do show up occasionally, even if you have to drive a bit to get to one. Put a reverse ad in your local Craigslist stating "looking to buy nailhead Buick engine."

I would reconsider the dynaflow transmission though, they are not all that crisp. I would either put an adapter back there to mount a stick setup or a Bendtsens adapter to put a late TH 350 or TH 400.

Be prepared to spend some money on the initial purchase and also in rebuilding it though. Any time you play with an oddball (I mean that in the sense of being different than a sbc or sbf) you are going to spend more money. I have a 394 Olds that I rebuilt for some future project and have about $ 3K in just a good rebuild. These Buicks, Olds, and Hemis cost a bit more than most to do but the wow factor is worth it IMO.

Don