If this is the case, I suppose it is worth it to buy some extra fans. How many and of which quality, is too complicated for me. I've found 2 fans that seem appropriate, I'll supply a link.
Number 1, a Cooler Master Sleeve bearing without leds for 6,95 from the site where I am getting my new rig from.
Number two, an Antec Tricool with blue leds costing 13,95 at the same website.
I like the cheapness of the CM fans you linked to( I got a 4-pack for $15 USD not too long ago.) Only thing I don't like about them is that the holes go all the way through, prohibiting use of typical silicon mounts so you must use screws.