Defenders David Artell, John Johnson and Nana are all ruled out along with midfielder Luke Guttridge and striker Alex Nicholls.
Boothroyd has no fresh injury or suspension worries ahead of the trip but is unlikely to have anyone back before the new year.
His side have been forced to train at local football centre Goals this week for use of their 3G surfaces in an attempt to beat the cold conditions.
Former Gulls striker Adebayo Akinfenwa will look to add to his four goals in the last five games, and 14 for the season.
The Cobblers travel on the back of three successive defeats in all competitions and Boothroyd admitted defeat to Cheltenham last week was a hard pill to swallow.
"It took me longer to get over the Cheltenham defeat than any other game this season," he told BBC Radio Northampton.
"We're so near to being a really good team. That might mean a couple of players coming back or joining us, or more work on the training field. It's probably a bit of all three.
"This is a key time in our development. Improvement is being made but we want to improve our away form, certainly."