Check out
www.dickmillerracing.com/Engine_page.htm and
www.mondellotwister.com for Oldsmobile performance parts and crate engines. Also you should post your question in the Olds forum. Stock compression was quite low at 7.7-1 and you might consider buying a 455 olds to build up as it would be cheaper and more powerful. Plus the 455 will bolt in with your current engine mounts.