I'm an importer and had to sign up to add my two penneth.
I think the Polish will eventually bring them all back from France and the bottom will fall out of the market before these bikes run out. There were 1000's sold, likely 10k plus, many just sitting there in nice dry garages. Crime wasn't that bad over there and very low in the south.
I originally used to import cars into Australia then moved back to Europe with a French girlfriend. I have a stash of various European DTs to sell eventually among other bikes. I'm in Japan at the moment filling a containter with older rare Japanese stuff and a modern hybrid car underneath to sell to the Taxi drivers in the UK.
You do see dealers here buying 125s but most were treated like the UK bikes and all seem to have surface rust as a minimum. You've all seen the nice Jap imports with dealers and their out of reach asking prices. Fair enough if the bike is rare or unique which DTR 125s arn't.
When in France I buy 2-3 two-strokes every time I visit her as we're in a part-time relationship now. I make the most of visiting France and really enjoy it otherwise I'd get sick to the back teeth of the driving.
The French are generally nicer to deal with than people in the UK. They often don't describe their bike that well though. This works both ways as you can get one that will pass as 'mint', sometimes with 20k on the clock, described as average. Loads of these get clocked mind when they arrive in the UK. In the UK everyone is trying to make money out of each other, it's difficult for it to be enjoyable and life goes by too fast.
My advice is to get on Facebook and offer the Polish importers £1500 for a good clean DTR that needs no more than a service. The UK is notorious for mugs paying stupid money and dealers adjust their prices up accordingly. High prices eventually put people off and they'll move onto something else. Like the Ford scene will be left with just boring rich people and their 50+ grand Cossies. 20 Grand RS Turbos. 10 grand XR2s and 3s.
Definitely don't pay more than £1750 for a good one unless it's a one off condition bike. There's just too many about and or ready to be imported.
Sellers taking the mick with high prices on UK ebay doesn't help as there's always plenty of drivers on the roads ready to pick stuff up as the prices rise. They are like hawks. Also you can see Germans are watching the UK market and adjusing their prices upwards accordingly just like they did with the RDs. If everyone stuck to their guns and refused to pay the high prices then these bikes could remain good value. The DTLC YPVS are still good value and so are the TDR 125s and very underated for being so similar to the DTR.
One thing I don't get is 'scrimsmustang' surely the same ebayer asking towards £3k for a French import then seemingly trying to put people off buying them in France 
even going as far as claiming us importers were "buying for peanuts" and "making a killing" on 'imports' on the auction description trying to promote a "genuine UK bike"
The only way of making a 'killing' is to use shipping containers and fill with genuinely rare vehicles.