Personally I would go with the $1000 solution and see what transpires. The $1000 can also be applied to replacing timing belt and very likely smashed valves but 300k is a well used engine and likely not worth it. I don’t see how you are going to find a 94/95 engine with minimal mileage and I believe the dealer. The likely case is in 1996 it went to an OBD-II engine which has revised emmissions which your car lacks the sensors/wiring harness and computer to run.
If this is an automatic transmission car and original I would expect that to go and essentially total your car. Spend the minimal amount of money and see how far it goes.