If your current Roku model is not on the supported Roku list in the following article, "Frequently asked questions about SlingPlayer for Roku", that Roku would not be supported. This is indicated under the selection "Which Roku models are supported?".
What I can suggest is to make an Enhancement Request for that model to become supported on the community forums page.
Sling Media Moderation Team
Hi Kevin, after contact Roku call center, they inform, that the diferences
between the roku models are:
"The alphabets varies based on the place where you purchase Roku.
R-players purchase from Roku.
X-purchased from retailers.
EU-purchased from Europe."
The equipment are the same...I have one from Roku, the 2700R, and its
working fine...maybe sling should update in the list...thx
2014-09-28 19:49 GMT+01:00 kevin.sling <firstname.lastname@example.org>:
Slingbox Answers Forum
<https://community.sling.com/?et=watches.email.thread> Roku 1 2700R
works with SlingBox M1?
reply from kevin.sling
in General Slingbox M1 Questions - View the full discussion