My name is ***** ***** I would be happy to help with your "Old Foley" Kent teapot.
Thanks for the helpful photo, I can see exactly what you have.
Ye Olde Foley Ware was a brand name used by the James Kent Pottery, Fenton, Staffordshire all the way through the first half of the 20th century. In the mid 1950s the name changed slightly to Old Foley (no 'e' o the "Old") so if that's the spelling, and if this is the mark, then your teapot dates to circa 1955-1970.
Sadly the secondary market (auctions & on line sales) for this Old Foley "Harmony Rose" pattern does not seem to be that active so the value of your teapot is not going to be a whole lot, I'm afraid.
This set with creamer and sugar sold on line in 2013, for instance, for a mere AUS$20 which is probably a little on the low side. So I would give yours an auction value in the range of AUS$20 AUS$40. It therefore has a full retail value (if you saw it for sale in an antique store) of $80. This is also the replacement value for insurance purposes.
I do hope this helps!
Please let me know if I can be of further assistance with this, I would be glad to.Best wishes,Robert.