Welcome to the forum Johnyg !
I'll jump in here before the resident guru answers and venture an answer. It would be a good idea to do a compression check to determine the over-all health of the engine. You might end up needing to spend part of your budget on the short block or waiting until you have more funds. If the short block is not in reasonable health, then it doesn't make much sense to go ahead with other mods.
Without going into the short block, then I would suggest a good dual plane manifold, headers and better exhaust system. If you're going to the expense of heads, then your price just jumped another $1200, maybe a little less if you're not wanting aluminum heads. At that point it start to make sense to a complete engine rebuild since it has 88k miles.
You shouldn't need a double pumper carb for the street, vacuum secondaries would be the best way to go.
How much are you wanting to spend ?
Good luck!