Thank you for sharing this info. I called their store and unfortunately they only have the one left which is listed on Gubroker. He said because it already has a bid on it, they have to sell it through there (completely reasonable).... and because its through Gunbroker they have to charge the 3% fee and tax. The search continues...Not quite under $3K, but the cheapest Buy It Now on an SP5 that I've found on GB.
I googled the store name and called them up to see if they would accept any online electronic payments without paying the 3%. They ended up having another in stock at the store (not listed on GB yet) which I was able to buy using a credit card without the 3% charge and no sales tax. Hopefully shipping tomorrow!
Definitely worth the time it took to do the search and make a phone call.