DPA 4061 family of miniature microphones

Why have these microphones suddenly started to cost a small fortune? OK they are quite good but up to £400 Each! I bought my collection for less than £400 (my service and repair not included!) and I have six of these miniature mics.. And DPA's new de facto violin mic (4099) is just a 4060 in a tube with some air slots to give it a more directional polar pattern! Tweek 'til your heart's content.. But won't this just colour the sound? Rather like singing through a toilet roll!