I certainly do not claim to know very much at all, but I doubt the authenticity of it, cheers Dennis
Not so sure of that Dennis

. It looks like a unit level mod. Pretty basic in design and construction.
Although slightly similar in configuration, it's not LRPV as the SASR used a different design. Apart from a single bolt for attachment to tub top capping, this mount has no restraint. The bracket/wheel would smack up against the side of the tub every time the vehicle drove over a decent bump. I suspect that the mounted wheel would be restrained at the bottom as shown on the Gunbuggy in the photo below.
It may be off a Gunbuggy

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