eBay is the best place to buy new stuff and to buy good used hard parts. For my current rebuild, I've purchased 4 brand new raw water pumps, each under 100 bucks each, 4 V6-14 TBolt modules, each under 100 bucks, 3 new tbolt distributors, each less than 95, a complete case of AR133 plugs at less than a buck each, OEM wire sets at 25 bucks each, GM EOS at less than 10 bucks a bottle, etc, etc.
My last boat was a 42 Carver aft cabin. I bought spare props for it too. Brand new Nibrals for 95 bucks each. And most of the new electronics for it as well.
I'd rather buy spares that I can sell later than to get to the point where I must buy at retail.