Joined: Jan 2008
Posts: 23,643
Likes: 1,107
From: Mans of NC & SW UT Desert
Bikes: 86 Katakura Silk, 87 Prologue X2, 88 Cimarron LE, 1975 Sekai 4000 Professional, 73 Paramount, plus more
+1 Cheapest route is either pick up a set of stem shifters at a co-op, or buy a new set of Tourney trigger shifters ($15+/-) and mount them on the bars. Lots of alloy bars out there with a 25.4mm clamp, which is another item from the co-op. Not sure what kind of co-ops or similar are out there in Europe.
You will need brake levers. Everything else will work.
Road brifters do not play well with most MTB front derailleurs. They work fine with RDs.