If that cam is really 268-272 at .050 duration that's race only / trailer car territory. Unless there's a $10,000 short block underneath, the engine will just blow up before that cam even starts to work right.
So agreed, I'd either regrind or just sell the monster cam or just set it aside.
With a "very limited budget", my approach would be, if the engine and current cam are good shape, leave em alone!
The intakes (I'd try both) and Fentons will be fun and add power even with a stock cam and its darn near free to try them. Tuning the carbs is where the gains are at and that just takes time, not big $$$.
