You can still buy stocks for the 336 from Marlin, or you can buy semi inletted stocks from Precision Gun Stocks, or Treebone Carving. You should also check Ebay, if you don't mind used stocks, as they are often for sale there.
Model variation
The Marlin model 336 will sell for between 200-350 dollars,depending on overall condition.
By including the serial number in your question,we will be able to answer when your Marlin model 336 was produced.
the cost 3030 cal 336sc
I just purchased one for $300. that included a Tasco scope and see through mounts. Stock had some small scratches but was otherwise in good condition.
$350.00 to 500.00 depending on condition
Between 200-350 dollars depending on overall condition of the wood and metal,and a good bore.
3030 is not evenly divisible by 9. However, 9 does go into it 336 2/3 times.
The R prefix to your serial number indicates that your Marlin model 336 rifle was produced between 1957-1958.
300-500 USD
Your Marlin model 336 RC(regular Carbine) will range in price from 250-350 dollars depending on overall condition,and a good bore.
You need to include a serial number to get a answer.