Use APKPure App
Get Handcent NextSMS Skin MoonBay old version APK for Android
Moon Bay skin for Handcent Next SMS
How to use:
Open navigation drawer->Handcent Services->Skin
Select the one you like to apply. Enjoy!
*** App2SD ***
This plugin support App2SD, you can move it to SDCARD from System settings->Application manager->Move to storage card