Sorry for being rude as well.
The natural philospoher:
Yes, as are the majority of houses in this country. It is not a problem, beyond one of paperwork.
The build regs at the start of the 20th century made real changes to housebuilding, helping to ensure better standards were met, in most cases. But as with many such things, they took on a life and momentum of their own, and no-one has really stopped to question the illogical maths behind many of todays regs.
Today we are at the point where at one end of the scale some BRs are about safety and utilty, and at the other end, some are about trying to avoid that one in a million case of problems down the line, and achieving that it at a cost of 1000x times the cost of letting that one problem occur and paying to fix it if it does. This is one of the reasons our house prices are so high - only one of them.
Look at our Victorian housing. Most of it is fine, no significant problems, yet they fail to meet todays BRs in more or less every single area. It simply isnt a significant problem.
A single insulated flue may not conform to paperwork requirements, but in terms of functionality it is actually better. More energy efficient, lower run cost, heats the house faster and more evenly, less polluting.
If you decide to live with it, you may need to remove and use more suitable paint. (There are other options.) But to remove the gas fire and fit electric to me makes no sense at all. Electric is 3x as costly to run, will cost money to supply and fit, and you'll gain absolutely nothing as a result.
Similarly, replacing the flue will gain you all of nothing.
NT