Casino chips for silver

I'm curious what the general price is across kingdoms for silver.  I've sold 21 M for 600k chips on the regular.  I've seen posts about other kingdoms selling 10 M for 600k.  That's a great deal for the seller!  I tried 15 M for 600k today and was told it was too expensive.  The guy responding said he sold 65 M for 15k gold or equivalent of  about 950k chips.  I think he's too cheap or isn't able to sell that often.  What's your price?