The only two engines choices I know of that will work with the stock transmission and stock engine mounts are the stock engine and the early JDM ZC (from the 1986-89 Integra and 1984-87 Civic/CRX, both sold in Japan). I don't think any other heads (besides the very similar ZC) will work on that engine either. If it's just a beater, I'd rebuilt it or drop a used stock engine in.