what are my realistic manual transmission swap options?

thank you for all of your replies, lots of useful info here. After reading through your responses and doing some other research i think its worth $200 or so to replace the 904 with an identical column shift unit for the time being. I can't express how ok i would be with hacking into my firewall and floorpan, this thing is rotten! but it sounds like way more trouble and money than its worth for me to try to attach a 5speed to a 360 in my $1000 car. it needs the repair anyway so i might as well fix it how i want it. Since a small bock and /6 have different bellhousings i don't even want to mess with it until i am ready for the v8 swap. With my space to work and mechanical skills i would rather just go with a 4speed and a small block so everything meets up nice and easy. or maybe in time i will do a fuel injected 5-speed swap from a ram or dakota (my dream). either way, i thank you all for your input and i will update on how my slow project is going.