Some thoughts on "indispensables"

I do really have to get onto the white/ivory top issue, and make some more.  This little ivory merino Tshirt that I am wearing (an old faithful from about four years back) has sprung a few holes.  Thus the necessity for a cardigan over the top...  Very very sad.  But looking on the bright side, an opportunity for me to introduce something new...?
Hmmm, see here's the dilemma, when you have something in your wardrobe which is nigh on indispensable, which you reach for over and over and over and wear to death because it goes with everything; when it has reached the end of its life, should one try to replace it with something exactly the same, or should one try to move on and seek out new silhouettes and colours, a new sartorial direction for one's wardrobe?  
I'm torn.  
Another little thing that is really almost dead is my little olive green corduroy skirt, which I keep wearing, but really really shouldn't.  It too is now looking pretty awful. ( When I do dare to wear something that is looking a little shabby and horrible, I can't help but the words of my Granny pop into my head; what if I was to have an accident?  What would the doctors and nurses at the hospital think when they see my hole-y top, or pilled and baggy cardi, or mis-shapen and bald corduroy skirt?  Tut tut...!)
But, I digress; what do you do about those indispensables in your wardrobe? when a really truly favourite basic has had it, do you try to replace it with a clone, or do you see the opportunity to go for new looks?


Details:
Top; Ezibuy
Cardigan; MNG, found secondhand (and covering up some rather un-strategic holes)
Jeans; Burda 7863 with minor modification, grape stretch denim, details here
Scarf; my own design, Patons ivory pure wool, details here
Shoes; Francesco Morichetti, from Zomp shoes