Urgh. Boiler is on the blink - Recommendations?

[Gazanimal]

Managed to get through Christmas (luckily) but now my 20 year old boiler appears to be on it's last legs.

Faulting when trying to heat the HW or CH which means at best we use the immersion heater on our HW tank which is expensive and not ideal.

Any suggestions for a new boiler, as I suspect this one is not going to be repairable as parts have been hard to locate previously. Bosch seem to have been a good recommendation, but switching to cheaper parts has damaged their reputation a little of late from reviews I've read.

Boulter Buderus 600-11R boiler (yeah I hadn't heard of them either when I moved in) Unvented Indirect System for reference

 

[Gazanimal]

Might as well get a heat pump with the grant

I was tempted previously with Octopus, but with the time it takes to get a survey done it'll take too long to get one installed and supplying HW etc as I suspect the boiler is beyond economical repair. In an ideal world, I would go Heat Pump and Solar panels.

All the other brands I know of, I used to have Glo-worm years ago. My main issue is trying to get hold of a heating engineer around here, some either can't help or never get back to you.

Also, don't quote via Boiler Central. They will pester you for weeks! 3-4 calls per day.