I definitely wouldn't replace with modern radiators, the tall ones.......wouldn't suit the room. I'd go for painting initially, i've painted all of ours in the same colour as the wall, admittedly just with paint mixed up the same as the emulsion. Valspar at B&Q do a great paint for indoor wood and metal, you can have it mixed whatever colour you like. I cleaned ours and painted straight over the top of what was there. Works a treat. I've always painted ours cold, not sure about painting when warm, never tried it.

Here is an idea of my room design(it was done on ikea and I didn’t do it right but the kitchen won’t be ikea it’s shaker/inframe look with white galaxy quartz countertop and coming 1/2 mtr up the wall. I forgot to put the radiator in but it is on the right across from the table at the end of the countertop

Thanks. The seat is 50cms deep and was originally designed by an architect to be a window seat. It still has the same solid support for the first 40cms depth, I've just removed the original decorative panel and replaced it with a very thin radiator. The old wooden front panel and supports would probably still have fitted back in place but I disliked it and threw it out, and it wouldn't have been easy to perforate. I'd been trying to avoid a metal screen, as I can imagine it will clang a bit if someone's sitting on the seat and swinging their legs. But it's a good idea apart from that. My current thought is to have a fixed panel in the middle and some hinged doors at each end of the radiator (for access) ,with the MDF attached to the front edge of the seat rather than fitted underneath. I'll go and take a look at those metal sheets thought :)

You could always get one made. A carpenter or joiner will be able to make one to your specific size. The decorative sheet material you see on the front of so many is easily available.