deadsea - 12:21 pm on Jun 27, 2011 (gmt 0)

is it possible / any idea to retain that URL in google index while i pass that URL to other related pages across my website temporarily (well not so temporarily)

If I were Google, I wouldn't want you to be able to do that. If your site doesn't have a product temporarily, I'd want to not send users to your site during that time period.

I would also be concerned that if you do get clicks from the SERPs, but don't have the product available, more users are going to return to google and check out other results. Google measures this and may use this as a negative signal in the algorithm for your site.