Shelley Jug

I would love to know a bit about this Shelley Jug that has come into my possession. It has a lustre finish & is approx. 6 1/2" tall. It appears to have a thistle image on the front & under this the words "Better buy than borrow". I have tried to find out about it on the web but failed. I believe from the stamp on the reverse it is quite an early piece. any info would be welcome as to where it originated from etc. thanks