Can we networking three UC500 on a WAN

On a Cisco 10720 router , some SFP are end of sale...My question is :If we replace the part 10720-GE-SFP-LH with  the SFP-GE-L does we have to upgrade the IOS or any other think to do ?Table 2. Product Part Numbers Affected by This AnnouncementEnd-of...

On a router Cisco 1721 who have a wic-1T module , can we add a hwic-1T ? because the Wic-1T is end of sale ?

I have attach my configuration for a UC 540 . I have somes questions:questions 1: With the UC 540W-FXO-K9 it is s include 8 users licences for UC and intergrating messaging , regarding the UC does i'm ok with the ipphone cp-7931=?questions 2: the 8 u...