I don't see why not.
Arnold Baker (the bible) 9.29 says that generally allowances are not paid to clerks, (other that unpaid clerks who are councillors)...
In any case, both Clerks and Councillors are legally able claim out of pocket expenses for things like travel, postage, phone etc.
I would suggest that your finance committee puts it on the agenda and makes a resolution to do so, with some sort of budget, so that its all above board and minuted - our auditor likes to see these things recorded!
(Note the difference between an allowance (taxable) and expenses (not taxable))
HTH