On another site after I did a google search, I found stitch count for this design. It is 77x155.
The recomended fabric is 32 count Sage Jobelan fabric, an evenweave. It is stitched over two threads on 32 count.
If you use the this fabric, the design size would be 4.8" x 9.7". You need to have 3" margin on the fabric for a framer.
That would have you purchase the 32 count Sage Jobelan in the size 10.8 by 15.7. Were it me, I would buy a piece 11"x16".
It is my suggestion to round the numbers a bit up. If you need the fabric and this size is not available, then buy the next biggest size to be sure you have enough. It is always good to keep your framer happy.

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