I can't comment on the dosages, but I can give you some sources of Co-Enzyme Q10 that may save you some money.
Q10 28g powder $55 (NOW Foods)
Idebenone 25g powder $30
Q10 28g powder $60 (NOW Foods)
Q10 100g powder $188 (economical, but only for the committed)
(Idebenone is Q10 derivative with similar effects to ubiquinone. Idebenone is better at some things than Q10, and worse at others. A suggestion might be to take Idebenone:Ubiquinone in a 1:1 ratio)
There are probably also bulk sources around, such as Paddymelon in Australia - when contacted, they say they can make provide smaller amounts, although the price/G increases sharply.
Some Co-Enzyme Q10 information:
Introduction to coenzyme q10
Coenzyme Q10 article at the Journal of Orthomolecular Medicine
Update on Coenzyme Q10 at the Journal of Orthomolecular Medicine
Research on Q10*
(*site no longer allowed to publish health information as per Australian law)