Mounting base for ar scope

I was recently given an older colt 4x21 handle mount scope (similar to the hakko scopes on cdnn). I have a bushmaster a3 that I have an aimpoint mounted on as my normal optic, but I was thinking of carrying the colt scope as a distance piece until I pony up the dough for a magnifier. Herein lies my problem.

I do not wish to mount the scope on the carry handle. If for some reason I need the distance ( varmit hunting, etc.) I would like to mount it directly to the flattop so I do not need to also remove my flip up rear site.

Does any of the manufacturers out there make a mount made to convert a handle mount scope to a flattop?

Thanks in advance.

I’ve never seen this. But it would be wiser to mount any optic to the Flat top instead of the carry handle. Holdover is just too ridiculous for such a short range weapon.