Hunter has bagged nine assists and three goals so far this season and Barton expects the 23-year-old to be hot property this January.
The striker-turned-winger has helped Town to 10th in the League One table and Barton thinks Pilley will have a decision to make.
He said: “Ash Hunter must be on virtually everyone’s list; he has been outstanding for us.
“We have got to be prepared for clubs in the division above and above that testing Andy’s wallet for him because he is a top player.
“You have got to have one eye on who you might bring in but you have also got to do the right thing by the good players we have got here.
“We have got a number of them but we have got a long way between now and January.”
Town now go into today’s match with Shrewsbury Town after a week that saw them win 4-0 at Doncaster Rovers before losing 2-0 against Rochdale in the Checkatrade Trophy in midweek.
Hunter netted and bagged another assist at the Keepmoat but was one of 10 players rested by Barton on Tuesday.
Paddy Madden and Ched Evans were reunited in a front two at Doncaster as niggles to both in recent weeks had not allowed them to play back-to-back games as they aim to build a partnership.
They have 10 goals between them thus far and Barton wants more competition for those front two roles.
One option is Ashley Nadesan, who has scored four times on loan at Carlisle United, and Barton is considering bringing him back in January as he looks to add competition up front.
He said: “I do really want competition in that slot.
“Chris Long was brought in to do that.
“We have only got three of them in that space really.
“It is something we probably need to be aware of.
“Going forward, we have not really got any younger players coming through in the striking spot.
“Sam O’Halloran is probably some way off challenging for the first team at this minute; he is developing in the (Under) 18s.
“We need to kind of fill that gap between, whether that is through Nadders coming back in January.
“He has gone out and shown that he can score at League Two level; there could have been an opportunity for him but we felt his development was better suited playing senior football.
“The key for me is we want to get that two up top because we feel in this league, if you go for one up top, teams then have an ability to then put the ball into your territory.
“We just feel attack is the best form of defence, especially in League One.
“Getting two up top allows you to press the ball from the front which can give your defensive side of the team a bit of a breather.
“If you have one up there it could tend to come back at you quite quickly.
“In the Premier League and the Championship you have to control the engine room in the middle of the park; that is the key to winning the game at that level.”
Tuesday’s defeat also provided food for thought in terms of Town’s midfield with Barton challenging players to learn from their displays.
He said: “Tuesday, I did not feel we went through the middle of the park enough.
“We lacked game intelligence in there, someone who has the ability to get on the ball; probably why the performance was where it was.
“We can now explain to young Harrison Biggins about how you impact the game – and Kyle Dempsey. There was a lot of learning for younger and senior lads.”