Just a thought really - my icon seats are generally fine, but has the inevitable wear on the drivers right bolster.
A re-trim or a local repair might be in order, but I’d like my seats to look completely OEM.
Any idea if it is possible to buy replacement leather covers off Mazda?
They are available as a general rule but your car being a special edition may mean that they are no longer available. You’d need to check availability at a dealership.
edit to add. Seen your car is a 2000 Icon so I doubt there will be an issue getting those covers, they were a factory fit seat. The price may supprise you though…
The price won’t surprise you, it will make you fall over.
Another alternative is a passenger seat from a scrapper in a left-hand-drive territory (USA, Canada, EU) - these are generally in good nick, like our passenger seats, and are not in much demand (like ours) but are in fact a drivers seat here! 
Hi - I have a 2007 Mk3 and the same issue - driver side bolster by the door - fabric is exposing sponge base underneath. I am not keen on covers that look baggy and saggy. Dont want leather. Is an OEM version available and how easy is it to get over the original base - looks difficult for a novice like me. PS live in West Kent.
Me to, 2001 Mk2, driver’s seat, worn bolster. I don’t see why a passenger seat cover wouldn’t do but I’m waiting to be corrected. West Kent too.