If you are only going to be using them to mark wood then the import sets will usually work fine at a cheaper price point. I use this Harbor Freight set and it has been fine. I usually use them every time I make something and they have worked just great. https://www.harborfreight.com/28-piece-transfer-punch-set-3577.html?_br_psugg_q=transfer+punch+set
The thing to remember even on the Spellmaco is if using on steel don't get all medieval when you hit the punch. While they are technically hardened the points won't stand up to repeated hard strikes in steel. You just want to make a mark that you see and can follow up with a real punch.
In wood, you can whack it as hard as you want. [big grin]
I got my set from Lee Valley which doesn't seem to carry it anymore. But the HF set is hard to beat for its price, especially the punches are seldom used.