I would just wait till the beetles mate and you end up with a ton more mealies... Save your self some money... It is easy to breed the Mealies... I have been doing with supers for a while and they are a bit tougher... But as you can see ... all you have to do to get the Mealies to Pupate is forget about them.
make sure the beatles have some thing like half a potato or something and keep them warm and i find they work better in the dark or they burry themselves.
Yup... and Tryme is right ... A couple slices of potatoe... I have also used apples... in there will provide food and water. Keep them in a dark warm corner of your closet and make sure it is not in a place where it will end up accidentally tipped... ( I learned the hard way... my cat tipped it and it sat all night... I was finding beetles and worms for days... had to empty out the entire room and shake out everything.) Just leave them to do there thing.. and remove dead beetles when you see them.