Cheaper alternatives to Printful for clothing to UK?

Hi all! I have just started a print on demand clothing shop of Shopify and I use Printful for fulfillment. I have 12 products on there currently.
The issue is with the sheer cost of printful. I list my t-shirts at £24, which is pretty average for t-shirts. However, after all the costs of Printful are added, such as fulfillment, VAT, and tax I make something like 78p for each one.

I understand that ultimately sourcing local is best but at the moment that isn't really viable for me due to my other job and there aren't many nearby that do what I want. Is it worth the hassle of moving all my designs over to another, cheaper site or just waiting to see if my business gains traction before I then look for local suppliers?
Thanks.