classical mechanics - Can linear momentum be considered a subset of angular momentum?

I was watching a video of a Prof Feynman Cornell lecture from the 60s. He was explaining angular momentum in terms of area traced out by a mass in orbit, and correctly noted that his explanation held true for a mass travelling in a straight line at constant velocity. It got me thinking about how the conservation of angular momentum must be related closely to the conservation of linear momentum. The challenge is that their units vary - $\rm kg~ m^2/ s$ against $\rm kg~ m/s\;.$

I only have an undergrad degree in Mech Engineering. So my maths is not too bad, but not up to the standard of many reading this question. Anyway...can it be easily shown, somehow that angular momentum translates to linear momentum as R increases to infinity?

Appreciate any help.