Some of these sites are setup simply to collect marketing data for resale. It is not uncommon for them to collect your information and then not complete the sale. Sometimes, they will have a very low price to entice folks. They are slightly different than the sites that try to steal your money by requiring person-person payment systems.
Whether this is one of those sites or not, I don know. While making sure you can use a credit card to pay is a good practice with an unknown site, it is not an indicator of these information collection sites as the sales may not come to fruition.
I was a bit TC guy prior to the S&W take-over. They were some of the most simple and flexible firearms at a reasonable cost. When S&W shut down production, the only option was gun broker and prices went crazy. I paid as much for used Encore action on Gunbroker as I paid for a new entire encore from TC when they were in production.