Where/who to donate Sun Ultra 10 in UK?

Dear All, I'm looking for ideas for passing on an old Sun Ultra 10, which I adopted when my old work was going to bin it. I installed Debian, but have the original OS media. Unfortunately, 3 moves and 2 kids later my time to tinker is non-existent, and my partner has made clear this needs to go before another imminent house move. I notice from my last attempt to boot that it now has the NVRAM battery problem, which a quick search tells me may be fixable. Ideally, I would like to hand it over to someone with more time/motivation (for free) rather than sending to the tip, but I'm stuck for ideas. I did get in touch with wildfire systems, who said it isn't economically viable for them even at zero cost. The Ebay market for these things seems more US-centric and registering for an account and dealing with postage is more effort than I would like (I live in Sheffield, UK). Any ideas gratefully received! Thanks, Pete