Plans based on quantity instead of duration

Hello !
My client wants to sell videos. These videos are classified by subjects. Each subjects include various videos.
He wants to sell plans based on quantity of subjects, for example :
PLAN A : 1 subject | PLAN B : up to 3 subjects | PLAN C : 4 to 8 subjects | PLAN D : all subjects.
In addition, each plan is likely to have a different duration, for example : 1 month | 3 months | 6 month | 1 year. But this must be setup automatically, I mean the user can't change the duration.

Is it possible to do it ? If yes, how should I setup the plans and organize the content (videos) ?
Would be easier to sell those video packs through eShop instead of Membership Pro ? Then setting up the duration for each pack would still remain a question...
Thank you for your help.

Hi Patrick
Both Eshop and Membership Pro are not suitable for this requirement, I'm afraid of:

1. Eshop cannot be used to sell access to video base on duration
2. Membership Pro allows you to do that. However, for each plan, it can only allows you to choose videos you want subscribers of that plan to to view, it does not allow you to define Number of videos which you want to allow subscribers to view

Tuan