Pay for pending orders in VM3

[nastal]

Hi!

Need a solution or some advice on how customer can pay pending orders from his profile, if order created by admin in backend via artio vmInvoice?
We use some custom products and it is not reasonable to put them inside our VM product database table, so fulfilled cart by admin is not that case. Or this option should contain possibility to add custom products (not listed in VM product list) in cart by admin.

My thoughts is to create custom plugin witch will add payment buttons somewhere between details_order.php
Click on payment button will triggers a plugin. Plugin will empty customer cart (in case it is not empty), creates a new cart based on pending order, parses data to payment plugin and keeps pending order number, so payment return url can switch order to "confirmed" after payment is done.
What you think: is it possible?