Given that you list 3 things wrong with the phone I would use the link to the repair estimate service to find out how much this will all cost. Then consider that your iPhone is kind of middle of the road in its anticipated lifespan. Also factor in are there new services that you might like that a newer model offers (such as AI?), or is there maybe a reason to prefer to stick with the 13 such as size?
Here's a link that does not force you to the UK version of the repair page:
For the iPhone Service Answer Center click here --> Choose Your Country or Region - Apple Support
Select your country.
For a cost estimate:
- Scroll down to "Get an estimate"
- Enter the service required
- Enter the iPhone model you have
- Enter the version of that model
- Click "Get estimate"
If you cannot get a good answer from that service, this support article has various country telephone numbers for contacting Apple for support and service ➔ Contact Apple for support and service - Apple Support For some countries look under “Other” listing at the end of each region. Not every country has telephone support.