WTB: 4 / 8 cell battery for X61(s) - or reliable eBay seller

[trmsw]

Good morning all,
I'm looking for a genuine battery in good condition (recent manufacture, low cycle count, high capacity) for my X61s - I could use both a 4 cell or an 8 cell. If you have one to sell please let me know by pm.
Alternatively, if anyone can recommend an eBay seller they've recently bought a battery from, I'd be really grateful. With batteries it's hard to judge good 'uns from the eBay feedback.