Need quote on moving a website

I have account with you guys.. VPS. I have another domain and website I manage that is VERY large.. and there is a members only area (CPanel) with MIVA store . I'd like to bring it over to my VPS account. It's very large though, and I'd like to see if you offer a service to move this and if it can be done w/out my members losing their access through our members only area. The website is www.billerswebsite.com and members only area with cpanel permissions/passwords through billerswebsite.com/enter

My account with you guys is under email [email protected] KLMEDIAHOST.COM
Can you give me a quote and tell me what would be involved with moving it?