Wanting to buy a single server boost with Nitro Classic

I'm currently subscribed to Nitro Classic through google and I wanted to buy a single server boost for this one server that gives perks for boosters.

When I tried clicking "boost this server"
this comes up:

Is there a way to buy a discounted (Nitro classic users get a discount) server boost without having to unsub ?
I still want to continue my nitro classic subscription and just want a single boost.