The 35-year-old striker has now played in two reserve games for the Spireites and has impressed Morgan with his effort in training.
Morgan said: “He played on Tuesday in the reserves at York City and was due to be in to train today but I think had a family issue.
“He’s been in and he’s trained really well. He’s an excellent professional.”
The former Leicester City and Blackpool forward, who has scored in each of the top five English divisions, is due to discus his future with Spireites boss Danny Wilson in the coming days.
Morgan revealed: “Gary and the gaffer will have a conversation possibly tomorrow or the early part of next week.
“You can’t beat experience and he’s got a wealth of that.
“He’s come in and his attitude has been spot on, he’s worked really hard, got a couple of goals in the reserves, we just need to wait and see what happens.”
Another player who has been trying to impress the manager this week at the Proact is midfielder Paul Marshall.
The 27-year-old has plied his trade in non-league since 2012, but has Scottosh Premier, League One and League Two experience.
Morgan said: “We’re just taking a look.
“We’ve been aware of him and with the loan window closing he’d be another who would be available to sign.
“We just wanted to take a look in training. He got in touch through his agent and knows Dan Gardner.
“We set it up and invited him in, we’ll see how that works out.”