How could I pay for additional publishing space for Editor?

I only have 315 Mb available and that is not enough for my core mod file. Since it actively uses assets from SCMR (Mass Recall), which is almost 1Gb total. I need additional space. Is there a way to buy it?

Of course there is workaround: create 3 additional accounts and split big file into 3 smaller ones. But this is not very convenient. I’d better upgrade my current account somehow to have more space available.