Just to update - in case anyone wants to do the same. I tried a Belkin wireless print server, which worked fine with windows, but the mac instructions were poor, and didn't work, and it was incompatible with my printer!
I did have success however with this one from
Edimax. It's wired rather than wireless which was an oversight but actually works well - as long as you have the router and printer within a couple of cable lengths of the printer. There is a wireless version if required. The instructions for mac are still wrong but there is a mac driver on the company website which works a treat. I can now print and scan from any windows or mac on the network. Perfect.