Johnson is now back in charge at Yeovil, for whom goalkeeper Weale made 191 appearances at the beginning of his career.
Weale, released by Leicester City this week with his contract set to expire, joined Northampton on loan at the beginning of the year with Aidy Boothroyd claiming at the time to have signed 'the best goalkeeper in this division' but was restricted to just three appearances due to a knee injury.
"It would be a very expensive one if we were to bring him in," Johnson told BBC Radio Somerset.
"Unless we can do a deal with him and he wants to come back home."