Doughty has already spent time training with the Saints squad and Lomas hopes to use his old London connections to tie-up the deal.
The Saints' boss said: "Michael was up to have a look around last week and we had a close look at him.
"Obviously I know Harry (Redknapp) well from our West Ham days and I know Marc Bircham (the London club's head of youth development) from my time at QPR.
"I think he would be a good asset to have, but a decision will have to be made in the next few days."
The Wales Under 19 international has already spent time on loan with Crawley Town and Aldershot.