Yes you can ( although you're not supposed to), it's not illegal.
eBay say...
"Counterfeits, unauthorised replicas (such as counterfeit watches, handbags, or other accessories) or unauthorised copies (such as copies of software programmes, video games, music albums, movies, television programmes, or photographs) are not permitted on eBay. Unauthorised copies include (but are not limited to) copies that are pirated, duplicated, backed-up or bootlegged. It is illegal to sell unauthorised copies of media.
Guideline: If the product you're selling bears the name or logo of a company, but it wasn't made or endorsed by that company, don't list it on eBay.
Breaches of this policy may result in a range of actions, including:
- Listing cancellation
- Limits on account privileges
- Account suspension
- Forfeit of eBay fees on cancelled listings
- Loss of PowerSeller status
What about replica coins for collectors?
Any "reproduction" "replica" or "copy" coin (UK or foreign) must be plainly and permanently marked with the word COPY."