Afraid not, a friend of my and myself actually tried contacting some of the old shareware companies
You should have ignored them. Anyone has the right to distribute shareware. You do know how shareware works don't you? If so, I don't understand why you even contacted them and I expect they didn't either. Here is the first Google definition I've found
Perhaps there was a misunderstanding here. Shareware can be upgraded to fully paid versions by, well, paying. I guess that these companies were assuming, by your contacting them at all, that you wanted to pay for the upgrade to the full version. So it is hardly suprising if they were taken aback by such a request, and that they no longer had the full version of this ancient DOS stuff by their right elbow.