The Australian turned down the opportunity to move to Ibrox along with Templeton on the final day of the transfer window in August. However, the 23-year-old has rejected the offer of a new deal from the capital club and now looks certain to move on when his contract expires in the summer.
Despite their transfer ban, Rangers are allowed to speak to free agents from next month and then register them on September 1.
Templeton revealed he has been in contact with McGowan in recent weeks and is hopeful he will join him in Glasgow next season despite their lower-league status.
"I feel for the boys at Hearts because I know what it's like," he said. "Coming up to Christmas, it's difficult. We did it last year and it was hard. I do feel for them, but I'm at Rangers now. I am enjoying my football and everything is good behind the scenes.
"I still text a few of the Hearts boys to see how things are going. I was very good mates with Ryan McGowan and I keep in contact with him. I texted him the other day to ask him what was happening and to say I'd like to see him here in September if he is still a Hearts player this summer. He just said he would wait and see what happened.
"Ryan is a great player and I think he will be away from Hearts in January. Maybe someone down south will take him as it seems Hearts are struggling and will look to offload a couple of boys."
McGowan rejected the idea of a move to Rangers in August due, in part, to concerns that playing at a lower level would jeopardise his place in the Australia squad. The defender had just made his debut for his national team in the 3-1 defeat by Scotland a fortnight earlier.
However, Templeton, who earlier this month returned to the Rangers first team after recovering from injury, has told his friend he enjoys life at Ibrox. "In August, we were coming up from Liverpool when we found out what was happening," he added. "I spoke to Ryan and then saw him that night at Murray Park.
"It wasn't right for him, but it was for me. I'm not sure why Ryan felt that way. I think it was maybe because he was in his international squad and felt going to the third division might affect that. I think that was the main reason and that he felt a bit rushed by it."