Hi
In general most of the online spare part sellers get the part directly from the brands themselves and send it to you, if a spare part is not available from one online spare part seller it is unlikely that you will get it from another online seller, I had to look for a lot of spare parts myself and I noticed they mostly disappear at the same time from all online sellers. The best would be to look for a second hand one online specially on eBay listed as "spare parts" which means it is not working and the buyer buys it only to use some of the spare parts from that.