So far this year you have opened 8 threads, and gave no replies. Why PM me the details of it's 4x4GB and you are in the UK? Why not reply with that info?
Seeing as you are in the UK, I'd check ebay for that country. Use what you find there for guidance on what to sell yours for. Are you going to use Ebay? Do you have craigslist or FB groups over there for selling things? Check your sold things there for price info. Or just list it and if it doesn't sell start dropping the price. Someone will buy it at some point.