Obviously the good people at Spondoolies would be the best bet to get matching original hardware, but I have no doubts there are others who could make that connection for you.
If you're willing to pay for it then you can buy all their PSUs off the shelf from [specialist] retailers. Exact model numbers are in their respective guides, although I'm unsure if the two variants of SP31 PSU are the same as the two variants in SP30s. SP35 had no variant but a different 1600W.
Be warned though, they are crazy expensive due to their compact package, and part of the reason SP3Xs were such good value /expensive for ST to manufacture. When they are / were no longer viable for mining, you had $400-$600 worth of PSUs to resell.
Did you link the specialist retailers for our good man here quakefiend? Maybe I missed it?
I cannot see Guy caring at this point. If the units were under warranty he may want us to be sure we put that disclaimer out there. Since next gen B2B, etc is the priority and understandably if that is what they must do to make a profit for investors, then it should be OK. Right?
I mentioned J4bber because I purchased several of his products since there were no others like them on the market. Finsky is my dealer for North America on the 2880 PSUs and J4bbers B/O boards along with the fact he did S4 PSUS
(which I lost faith in your employer getting me a drop in replacement under warranty which would function at stock for no less than 90 days. Remember they tried to give me a 2000BB because I was telling them that PSU I picked up from sidehack with his awesome BO board worked flawlessly for my S4s? I told them that was unacceptable from the manufacturer - wanting to send me a 30 - 40 dollar PSU which didn't fit.) I'm tired and getting ornery heh I'm still pretty butthurt over that whole thing as well, but not so much now. I mean I know doing business with them will always be risky for me, but it is what it is.
Maybe I will get another opportunity to own more Spondoolies equipment? I can wish heh. Even if I am only able to power a couple of miners here I would get them fast and wouldn't run the oven if that is what it took. The quality is impeccable on my SP20's. No other miner I've owned comes close to them. They simply built a miner in a class by itself when it comes to comparing offerings from these two companies. No contest in quality and customer service imo. So I must do my own research, but I have to think they are high end PSUs when considering the history of their products. They make great choices in the right areas. No doubt something which can move on up is good for miners so we can wash and recycle, but I've no doubt those PSUs with that interface was done for the right reasons, IE maintaining the size and supplying a consistent rail I'm betting.
Anyway J4bber has / had a drop in for those and I'm sure he could get something a little more cost effective if quake asked. I cannot speak to one or two units so def post up what you know to help this quake get the best for the best price.