Searching for Rotring Cleanser

The equipments I need to draw are a piece of paper, a pencil, and a set of Rottring pens. These technical pens have been my best friends from outlining my sketches. Since I haven't been using them for 3,5 years causing drying ink blob at the edge of the pens.

I have been searching the cleanser in a Rotring booth in Jakarta but the product has been run out. The booth keeper suggested me to wash the pen with hot water to wash away the drying blob. I did. Out of 3 pens only 1 works.

I called the same store. The same booth keeper said she will contact me after making an order to the producer. Few days later she sent a text message saying the product has been discontinued. SIGH. Should I buy a new set instead?

A whole new set costs IDR 700.000. SIGH. That's god damn fucking expensive!!!