Slightly bent rear-hanger (steel bike)

I am in some distress. I had a rather odd incident yesterday whereupon the chain of my bike came free and proceeded to wrap itself around my freewheel, pulling the rear derailleur upwards and appearing to slightly bend the rear mech/hanger in the process. The sprocket seems fine, not sure about the derailleur itself, and I'd have thought the chain's been stretched. Fortunately, I wasn't travelling at speed and stopped pretty much instantly - as such, the rear hanger is only bent inwards slightly. Still, it was a bit of a mess and the indexed gears are now all over the place.

This is the bike we're talking about: about 25 years' old, 126 mm rear spacing, Columbus (almost certainly SLX) tubing, Shimano 105 group.

https://www.flickr.com/photos/81054124@N00/8672479106/in/set-72157631896780921

I would like some advice.

First, is this a terminal condition? By that I mean can the rear hanger be straitened with some ease, how is it done, and how much should I be looking to pay for, if indeed it does need to be done 'professionally'?

Next, are their secondary issues that I should be on the lookout for? (The seat and chain stays look complete unaffected, by the way - like I said, this was a low speed incident.)

Third, does anyone know anything about Bikefix on Conduit Street, London? I outlined my position to them and they've quoted between £50 and £100 to sort out the rear hanger - I said I'd try and get a new rear derailleur on eBay, or the like.

Finally, can anybody recommend anywhere in London to sort something like this out?

I really am most upset about this - more than I ever thought I would be...

There is a tool for that - send me a PM, might be able to help.

Ben at Micycle Islington should be able to sort this for you.

It's steel, so the prognosis is good. And as above, there's a tool for measuring how badly bent it is. It should (famous last words) just be a case of gently bending it back.

I can envisage that trying to turn it outwards could apply negative pressure on the drop-outs themselves. A such, I can imagine you need to clamp the bike somehow to avoid this?

I had a steel frame with a rear hanger that was bent 45degrees across the deraileur thread.
Roberts fixed it perfectly.
£100 sounds steep.

To be fair, the guy hasn't seen damage yet - he could look at it and say £50 should do it. I'm just trying to get an idea on who's capable of putting it right. I'll worry about the cost later.

When you say 'Roberts' who exactly do you mean, and how much did he/they charge you?

It only sounds slightly bent so it shouldn't be more than a five minute job to straighten with the right tool. Don't even need to take the wheel off

Got it straightened for the reasonable sum of £15 by a guy near to me who hires bikes mostly, but does minor repairs on the side. Just need a new chain and rear derailleur, which shouldn't break the bank.