Yes, it’s a Vespa with a great big fuck-off gun. An M20 75mm recoilless rifle, in fact. How many kinds of awesome is that?
It’s a ACMA Troupes Aeról Portées Mle. 56. There are more pictures at that link.
It seems the French didn’t have a great deal of defence cash to spare after WWII, but Vespas were dirt cheap – about $500 – and the 75mm recoilless rifle was surplus. So with typically French inventiveness and flair, they came up with this little beauty. About 800 of these were deployed in Indochina and Algeria. No recoil, so you could actually fire the thing from the Vespa. On the move.
Why haven’t they got these in HalfLife 2?
It’s because it’s difficult to use them in a railway shunting yard: http //purchasebrothers.com/Purchase-Brothers-v2-hl.html :-)