It's not that it's a bad idea dude.
It's something you have to decide.
The head being machined is a good start.
As for the hg..., well it really depends on what you want from the car and your personal driving style.
I wouldn't go with any thing less than a beaded HKS/MHG.
If you don't do something to the block..., it doesn't matter if you put a 30$
or a 300$ gasket on it.
A car like this that you don't plan to drop some serious coin on is just going to not even nickel and dime you.
It's going to 20$ bill you. From there it only gets worse before it gets better.
Until the inevitable happens. Which is.
You have 10k in a car that's worth 3k max bet.
You're still monkey'ing with keeping it running. It runs enough to keep you on the stringer then you end up stranded. Cause one of those 15+ year old hose clamps gives and you have smoke and death.
Nike express. Less you have a cell.
Then you get to start planning your build..., that if you don't do yourself it's going to cost you endlessly.
Then when you get it done finally. You have a new view for the car and are seeking an engine to swap into the chassis.
It's a viscious cycle
. I say this jokingly, but that is basically my supra testimony, lol.