No promises here - if such a system is to be added, it would either have to be created from scratch (which will take at least a few weeks of full-time work, at least if I'd have to do it - which I'd probably do), or we'd have to switch to another forum software that does have a properly working shop / money plugin. The one used on ACF was horribly outdated and had been unmaintained for years, and as far as I know / knew, there wasn't a proper alternative for it.
But that and this topic has been discussed (shortly) in another topic. Also, this topic belongs in the Suggestions & Questions section, this section is meant mainly for frontpage projects such as translations, not for suggestions or requests of sorts.