Where do you live? If in England, Trevor White sells Graham Thomas (I recently planted it). Great quality. Or Carbeth Plants on Amazon purports to sell it if you are feeling lucky. If you are in the US, I recommend a Facebook group called Rose Geeks where they will know
Wams I saw carbeth plants sell a Graham Thomas but it doesn't mention anything about it being a david austin rose. I've emailed them to clarify if it is.
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