I see a first post, welcome aboard Allhands!
Reason for swapping out F47m? Just looking for a different flavor?
Not knowing how familiar you are with Guild history, be aware there are 3 different flavors of D25:
Original version was all-mahogany flatback, transitioned to an all-mahogany archback ca. late '72 thru '74 or even '75, finally completely replaced by arch-back spruce top formula that lasted all the way through close of Westerly in '01, which is the most common by far and probably the one that most folks think of as the definitive D25 for sound.
I'm assuming you're looking for something older than '01-'04 but that was Corona era where they revived the original all-hog flatback formula.
The D35 Guildedagain mentioned was basically a "blinged-down" D40.
There was also a G37 arched maple back dread, revised as the D30 in late '80's, and even an ash-backed D46.
Here's a site to give an idea of the range of offerings from Westerly:
http://www.westerlyguildguitars.com/guitars.html
I'll let others vouch for reliable vendors but can suggest that if you see a specific piece you're interested in, don't be afraid to show us a link and ask for advice about it here, there's a ton of knowledge here and several folks who can advise if a particular seller's a good internet citizen.
There's also a pretty decent gentleman's trust to avoid sniping on a piece a member has expressed serious interest in, we even try to honor calling of "dibs" on a piece while the member's trying to get input about it.
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