Just did some checking and yes there are still a bunch of Yost American made vises but they are QUITE PRICY to say the least. For a 5" model they list for just under $1100.00. While I almost always buy American if available, most can't or won't be able to justify it in this case when you can get a 5" Wilton #745 for around $250. The tensile strength of the Yost is about double of the Wilton, but the 35,000 PSI of the Wilton is more than enough for most of us. Hey, if you can or are willing to go for the American made Yost it will last 10 lifetimes!
There are still Wilton Trademan 5 1/2" "bullet vises" MADE IN USA at around $600 list. Both USA brands can be found discounted on the net.
You also might consider buying a used American made Wilton, Yost, Athol, etc on Fleebay. Other than chipped paint which is easily restored, most of the older vises have survived quite nicely and can be gotten at great prices. As of this moment there are some very good buys listed on vintage USA made models.
Of all the imported vises, Wilton is more than likely the best of the bunch. I purchased mine 30 years ago (made in USA back then) so I am not sure just when they started to have them made where ever they are now days.