I know Paya and APS both work up here just fine. You have to be careful with currency if you're dealing with a US system wanting to charge in CAD. I believe APS has a checkbox for supporting DSD Multi-Currency, but with Paya you have to set up separate payment types / merchant account settings for the different currencies.
I don't know about options for other 3rd party CC providers...
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Kevin Moyes
Technical Systems Analyst
Munjal White Consulting Co.
Toronto ON
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