You can search on aliexpress or something. Very frustrating, when I searched for 48 v bike hub motors I got a lot of boat motors appliance motors gasoline motors and hubs without motors. If you find something your bank may not allow you to buy it. Mine did not.
In addition to the 5A current rating, make sure the fuse / holder you use is rated for the battery voltage as well. Most automotive type fuses are only rated for voltages up to 32V. Higher voltages can cause an arc, even if the fuse is blown.
And you'll want proper DC fuses.
Solar fuses are good,..
Check your fuse and fuse holder dimensions.
You've got the special white DC fuse showing in your picture.
That's the tiny phillips head fuse holder in a silverfish battery. The round cavity is about 17mm wide at its narrowest point, and the round cap is about 15mm wide.
How about this one on ebay? Looks like its a 15mm head. That's for the charger circuit. We had a fuse specialist at work when I worked, so I never studied up on the craft. I have blown this fuse and I just rummaged around in my parts bin til I found a 5 amp.
Measure your original fuse and fuse holder to make sure that it will fit.
Most of the fuse holders that I found on AliExpress came with a choice of fuse.
You might have the smaller shorter fuse/fuse holder?
The longer fuse holder might work if you've got space for a deeper fuse holder?
Try to order something where they show all the dimensions.
I think the standard is the bigger, longer fuse and fuse holder?