Creating a VPN using Openserver 5.0.6

I am trying to setup a VPN to my network to allow someone to access files that we are working on and for me to access remotely.

I have a OpenServer 5.0.6. system running all the time. First, is it even possible? If it is, how would one setup it up?

5.0.6 comes with Visionfs, which is a SMB networking product, although it is not encrypted.
SSH is available, although not part of the original product. With SSH you have remote telnet (putty) , ftp(winscp) and Xwindows (ming) available.
Where can I get SSH for earlier version of Openserver 5.0.X?

Thank you for the tip, I will give it a try. I have a FIOS firewall and the ports for telnet and ftp are forwarded to my Unix server. Would VisionFs be better that that?

No. After re-reading my first post, I think you should ignore Visionfs.
Just install ssh, close port 23 in your router and open port 22.
Assuming the remote clients are MS Windows:
install putty PuTTY Download Page
download and install the installation package of winscp WinSCP :: Download
and Xwindows Xming X Server for Windows - Official Website
although this requires a little additional configuration on the SCO end.

After spending most of the day Saturday researching this topic, I decided to move the whole thing over to my FreeNAS system.

Thanks jgt on replying to my question. I may do what was recommended to add flexibility.