Most of that seems realistic, though if you were willing to buy a used 75g from Craigslist, in a city the size of yours, you should be able to get one for under $100.
As for substrate, consider pool filter sand. It'll cost you $20-30 total.
Unfortunately, you might be under the mark for filtration. If you were to buy one large filter for the 75g, you'll probably spend more than that. If you wanted two cheap (SunSun or Odyssea) filters, $120 is accurate.
If you wanted to hang a cheap plywood canopy, AHSupply retrofit fixtures and bulbs (top of the line reflectors) will cost you significantly less than you've budgeted.
And one other thought - a 90g tank has the same footprint as a 75g, with a few extra inches on top.