Sorry to be tardy on this.

Yes, your example will work fine. The thing to remember with heraldry is that unless an item is specified 'exactly' then artistic licence is allowed. But even then, there can be great leeway - all blues are Azure and all reds are Gules. Strictly speaking the strap should be leather, but men learned over a thousand years ago how to dye it. So the colour is up to you. The buckle and furniture should be brass, but again, yours could be made out of silver or even gold.

This sounds like a fun exercise. It would be nice to see a photo-journal of it being made - step by step.

Regards

Chas