My website is getting long in the tooth - looking for recommendations for ecommerce hosting

My website is built on pretty old technology, and I'm being told by my hosting provider that they'll cut me off in the not too distant future. I'm looking for recommendations for an ecommerce platform that caters to foundries, or failing that, a hosting provider that caters to software sales in general. 
My main concerns are performance and security. I would also need to be able to set up some custom pages to try out fonts, etc., not sure if that rules out some of the boxed solutions, like Wordpress. 

Has anyone here had any good experiences?