Unfortunately the items in the catalog are unavailable for purchase, and maybe it's common knowledge but the products themselves remain in the wishlists even when not bought.
What that means, is until they are removed completely, there is certainly a way to access them, and as you stated the association to the disabled user account is still there, the only limitation is the search function of the imvu shop itself.
In short the search tool can be made.
@sonson : was the one you found a downloadable app or just a search function on the website behind a paywall ?(there is no point for anyone creating an actuall app for that, unless idk...they just want to work more)
I just checked out of curiosity all the info that imvu allows to be accessed by a normal user, and I have a hunch it's pretty much the same system preventing nonAP users searching for Ap products that filters the catalog of disabled users.
Those people charging for this have something that is pretty difficult to obtain, unrestricted access to imvu's database, most probably developer credentials.
And just as a personal opinion, that won't last for very much either because of the new imvu client I heard is in development, along with the new creator studio, that will change the way they think their security(imvu that is).
So whoever wants to cash in on this kind of services might need to do it fast.