The 25-year-old scored five goals last season but missed the final three months with an ankle injury which required surgery.
Holmes will be out of contract at relegated Barnet in the summer and O's boss Russell Slade is monitoring his situation as he looks to build on their seventh-placed finish.
Slade told the East London Guardian Series: "Ricky Holmes has been injured but he is someone who is on our radar.
"There is a list of strikers and midfielders we're looking at but not so much in defence because we've got plenty of cover there."
- Sports & Recreation
- Disease & Medical Conditions
- Ricky Holmes
- Russell Slade