Replacing fuse

6.3A is a standard size and all the audiophile fuse manufacturers make this size -- Synergistic Research red/black/blue for example all available in that size
https://highend-electronics.com/products/synergistic-research-blue-quantum-fuses?variant=44898590531

Bought the fuses from Parts Connection located in Canada on sale, which makes the sizes and values limited.Know there are correct size fuses but didn't want to spend $50 or more for one fuse.Its a Hi Fi tuning fuse which many have for sale but none have the size and values needed.

No. The design engineer knows the expected fault current and from there determines how much time to melt the fuse, and that corresponds to 6.3 amps for your device.

Hmmm. So you want to buy a fuse on sale, save a few bucks and as a result burn your house down ... makes a whole lot of sense! 

Don't put in the wrong fuse -- the warranty is immediately void, and you create an electrical risk

It will work ... but the fuse isn't doing the job it's intended