Howdy,
As Raion mentioned, I have rebuilt Indy PSUs, ready to go, NIDEC Brand.
https://forums.irixnet.org/thread-3332.html
Now the big issue, I'm in Seattle, Washington State, USA and you're in another country. As Raion has advertised (due to the mouse pad project) shipping internationally became an expensive task.
In terms of ruining your Indy, I've not yet SEEN an Indy ruined by an aged-out PSU that didn't literally start smoking itself, if you didn't see smoke/smell...you're probably fine. I cannot speak to hard drives, but the Indy Mainboard runs mostly on 3.3v and that's normally not a big issue in failures (that' I've seen). Since you're on 220V, I cannot test on 220V, but there's no switch or selection - so it should just work. 220V switching PSUs often have to have a higher filter cap voltage then the systems running off 120VAC. We've certainly seen a few systems (namely Indigo2) be shipped (claimed working) from US to EUR only to have them smoke on first boot due to not being tolerant enough (anymore) to handle high voltage input. So you're not the first, nor will you be the last.
Likely the PSU is shutting off due to low-output voltage (dips) or swinging voltage (high ripple). Given the cost of SGIs, I NEVER RECOMMEND people keep playing with the power and multimeter checks, every boot with bad power could be your last. I'm unaware of any instance where the mainboard was doing this by itself, likely it or the PSU's own systems, are noticing a voltage out of tolerance and issue a shutdown as an uncorrectable voltage output. It's more likely your mainboard voltage is sagging when the PSUs heats up. This nearly always due to filtering components being too weak.
I will say that used Indy PSUs may be cheaper, but poor power regulation makes the mainboard work very hard and I've seen tantalum cap failures on the Indy mainboard due to poorly regulated Indy PSUs (but they were fixable, thank goodness). I cannot make any real-life guarantees but my expectation, with the quality of the components I used and the thoroughness of the job, there is no reason (stored in normally heated home) that these rebuild won't last just as long as the original parts did.
If you want to PM me with your address, I can do a shipping rate calculation. I can also suggest that perhaps you can amortize your costs by buying more than one rebuilt PSU.
Since you've recently done some shipping between USA->NZ, perhaps you have your own recommendations on that. The PSUs will be packed in an expanded foam shell and boxed. I can pack two PSUs per box I use (I believe they are 8"x8"x22", I'll recheck that). Due to Indy PSUs being so long, there is no flat rate box (even domestically) for cheap USA shipping. So the situation is what it is.
I'm flexible and obviously once we know the shipping rate, there is likely a deal to be made here. Believe me, I don't like shipping costs any more than you do! It sucks, but these PSUs are like 25+ years old, they were never designed for this long a lifespan and really, held up well over time, considering.
Feel free to PM me with questions or inquiries regarding Power supplies. But yeah, due to it's long size, shipping will be oversized.
Also, if you plan to be visiting the USA again (you alluded to doing so in your post), remind yourself and you can contact me and I can ship to you then to a friend/family member to hold shortly before your arrival? So if it works better to just revisiting this during a holiday visit to the USA or something, you can definitely pack them back in a suit case and their declarative value is pretty low, I'd think you'd be fine that way as well.
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