Do you plan to play the basic 3D games like gloom etc?
If not all you need is a ram expansion or the aca-1220 if you have a hard time to find a decent ram expansion.
You can play most whdload games without an 030.
So the cheapest route depending what you want to do is a ram expansion, 4 or 8MB trapdoor expansion will get you quite far for whdload.
this is very true as I have a Blizzard 1220 @33 with FPU & 4MB that works great with WHDLoad. Actually played Wing Commander a while back and I was surprised it held its own compared to my Blizzard 030@50-32MB (though obviously the 030@50 was much smoother when there was more than a few fighters around you :-)