Is the current embellished – non-Shariah-compliant – attire excused for a temporary period until the full Shariah-compliant attire can be provided and purchased, given the current lack of means?

It is not forbidden for a woman to go out in patterned clothes unless they are eye-catching and cause fitna (temptation/strife). If they are not so, then there is no harm in going out in them. However, if they are eye-catching, then it is not permissible to go out in them. In the event that no other clothes are available, going out should be limited to necessity or dire need until modest clothing becomes available.