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You could try the GSO SV 68-degree series. 1 1/4's are 15mm, 20mm, and 2" are 30mm, 42mm and 50mm.
They should be OK in f6.7 optics. Andrews have them for 10% off at present...
The Long Perng planetary series (same as Orion "edge-on" but 1/2 the price) are excellent, with great eye-relief. 3mm-18mm available also at Andrews.
The "1-2-4 rule" is a good one to go by:
1 mm exit pupil for high magnifications (globular clusters, binary stars, bright small planetary nebulae)
2 mm exit pupil for galaxies, open clusters, and details in bright emission nebulae
4 mm exit pupil for low surface brightness objects, and for very large objects.
All the best,
Dean
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