I have the 13" late 2013 Macbook Pro i7, 8GB. It is working perfectly fine, and as fast as it was on day one. Never replaced a single thing, and never had to do hard-drive wipe. The only problem I have is that, it is a 512GB SSD, and I have no free space left.
Sintech sell adapters via amazon US/UK etc for about $15 that allow you to take a regular NVME drive (which are VERY cheap just now) and adapt it to the apple SSD hardware interface. You can have up to 2TB of faster-than-ever storage. You'll also need torx screwdrivers to open the case.
If you do some googling you will see there are two versions, and depending on the size/shape of SSD you are buying it may be better to buy one rather than the other.
If you do more googling, people have tried various drives and report on performance/compatibility etc but generally compatibility is good except with some samsung drives.
I have an i5 version of this. Bought it from the refurb store in 2014 and it is the best computer I have ever owned. Unfortunately the keyboard is getting a little finicky, presumably from dust. In any case 6-7 years is a pretty impressive life span for a notebook in my opinion.
