Hi Tam,
There is no updated version of the K1000, and probably never will be.
It would help to understand why you want a K1000:
Is it because it has a reputation for being a good camera to learn on? If so, you can easily find a used one in good condition on eBay or KEH. KEH is a very reliable place to buy used equipment:
http://photography.shop.ebay.com/items/Film-Cameras__Pentax-K1000-K-1000-as-is-repair-parts-broken_W0QQ_nkwZPentaxQ20Q28K1000Q2cKQ2d1000Q29Q20Q2dasQ2disQ20Q2drepairQ20Q2dpartsQ20Q2dbrokenQQ_catrefZ1QQ_flnZ1QQ_fromfsbZQQ_sacatZ15230QQ_trksidZp3286Q2ec0Q2em282?_trksid=p3286.c0.m282
http://www.keh.com/OnLineStore/ProductList.aspx?Mode=searchproducts&item=0&ActivateTOC2=false&ID=&Size=&BC=PK&BCC=1&CC=2&CCC=1&BCL=&GBC=&GCC=&KW=K1000
Is it because it's all mechanical except for the meter, so it will work even without batteries, and even in extreme cold conditions where batteries don't work? If so, again I'd look at a used one.
Is it because it was known as a good inexpensive starter camera? If so, any of today's entry-level DSLRs generally make better starter cameras. Pentax has the K2000, which is nothing like the K1000 (except for compatibility with Pentax lenses, flashes, etc.) despite the similar name:
http://www.bhphotovideo.com/c/product/585958-REG/Pentax_17314_K2000D_SLR_Digital_Camera.html
Or you could go with a used DSLR to keep the cost down. Any Pentax DSLR is a great place to start:
http://www.keh.com/OnLineStore/ProductList.aspx?Mode=searchproducts&item=0&ActivateTOC2=false&ID=&Size=&BC=DP&BCC=3&CC=2&CCC=1&BCL=&GBC=&GCC=&KW=
I see that KEH doesn't have many used Pentax DSLRs at the moment. Usually they have a lot more.
To keep the cost to a minimum, a used Pentax *ist DL (pronounced as if the asterisk were not there) is probably the least expensive good starter DSLR model:
http://photography.shop.ebay.com/items/_W0QQProductQ2520TypeZSLRQ252CQ2520ProfessionalQQBrandZPentaxQQMegapixelsZ6Q252E0Q2520toQ25206Q252E9Q2520MPQQ_dmptZDigitalQ5fCamerasQQ_sopZ15?_nkw=%28DL%2CD-L%29+-as-is+-parts+-repair+-broken&_sacat=31388&_fromfsb=&_trksid=m270.l1313&_odkw=%28DL%2CD-L%29&_osacat=31388
Good luck and have fun!
Greg