Yes you can pursue cs with ca by submitting 112. If you have made your mind about CS and are ready to work a bit hard to pursue both degrees then there is no need to wait for PCC result.
At least at inter level and for theory subjects module will be enough. For Direct tax you can refer book of Bharat publications or of Taxmann publication. For Indirect tax you can refer bangar's book or ajay jain's note (although even for IDT i think module is enough). For accounts you can refer books which you have referrred in CA Pcc.
Subjects in first group are - 1 General and commercial law; 2 Company/cost/Mgt. accounts; 3 Tax laws
Second Group 4 Co. Law 5 Economic & Labour Laws 6 Security Laws & Compliances
For fee structure refer following link
https://www.icsi.edu/webmodules/linksofweeks/REVISION%20OF%20FEES.doc
For centre address select your city in following link
https://www.icsi.edu/webmodules/homepage/map_icsi.swf
For details on the course refer following link of CS brochure
https://www.icsi.edu/webmodules/student/Brochure/CS%20Brochure%20for%20Regular%20Course.pdf
If you register before 28 Feb, you can appear for both groups of executive programme in december 10