Dai from Classicswede.co.uk does strut top mounts. They're currently out of stock at the moment, but you could always send him an email and check when they'll be in.
Here's a link:
https://www.classicswede.co.uk/Struttopmounting_340_and_360_Pair/p1733344_9867644.aspx
I don't know of any other place you can get them from. When dealing with Classic Swede, just keep in mind that Dai operates his business as a side venture to his full time career. He is a good man and I have never been screwed over by him, but he has limited time and it can sometimes be quite a mission to get in contact with him and can lead to delays with processing your order at times.
This is the number you have to call to reach him:
0011447824887160
Or send an email to:
dai@classicswede.co.uk