all I'd be able to run it from safely is a pi with a pruned chain (and without a constant connection)...
Somehow I was under the impression you need a full chain for this. What's the memory requirement? If it's not too much, a cheap VPS could do. Although I wouldn't trust those with much funds.
I've always wanted to run "something" that can fund any (small) LN payment request posted on the forum
within seconds. I already check all posts, but need the LN side of it to work.